Low HDL is a well known independent risk factor for atherosclerotic disease. As a result, there have been several attempts to develop medications to raise HDL. Specific targets include the inhibition of cholesteryl ester transfer protein, which plays an essential role in HDL metabolism by facilitating the transfer of cholesterol esters from HDL cholesterol to apolipoprotein B-containing lipoproteins.
Pfizer created just that drug. Known as Torcetrapib, it was seen as a promising therapeutic to increase HDL and potentially use in combination with Lipitor. Drug execs were hopeful that Torcetrapib would be another money maker for Pfizer especially in light of the fact that they will lose their patent on Lipitor in 2010. But in a recent phase 3 clinical trial, known as the Investigation of Lipid Level Management to Understand its IMpact IN ATherosclerotic Events (ILLUMINATE), it seemed to increase blood pressure; there also appeared to be a larger number of deaths in the drug combination arm. So the decision was made to halt the trial dashing the high hopes that investigators had around the country for the drug. Ultimately, the loss of Torcetrapib will likely amount to millions of dollars in lost revenue as well as cost many their jobs.
Smerd, R. Pfizer Shutting Lights on Illuminate Study, NYU Clinical Correlations Vol 3 #5 December 4, 2006.